07af1bab70
This updates vendored runc/libcontainer to 1.1.0, and google/cadvisor to a version updated to runc 1.1.0 (google/cadvisor#3048). Changes in vendor are generated by (roughly): ./hack/pin-dependency.sh github.com/google/cadvisor v0.44.0 ./hack/pin-dependency.sh github.com/opencontainers/runc v1.1.0 ./hack/update-vendor.sh ./hack/lint-dependencies.sh # And follow all its recommendations. ./hack/update-vendor.sh ./hack/update-internal-modules.sh ./hack/lint-dependencies.sh # Re-check everything again. Co-Authored-By: Kir Kolyshkin <kolyshkin@gmail.com>
101 lines
2.8 KiB
Go
101 lines
2.8 KiB
Go
package systemd
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import (
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"context"
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"fmt"
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"sync"
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systemdDbus "github.com/coreos/go-systemd/v22/dbus"
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dbus "github.com/godbus/dbus/v5"
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)
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var (
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dbusC *systemdDbus.Conn
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dbusMu sync.RWMutex
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dbusInited bool
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dbusRootless bool
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)
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type dbusConnManager struct{}
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// newDbusConnManager initializes systemd dbus connection manager.
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func newDbusConnManager(rootless bool) *dbusConnManager {
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dbusMu.Lock()
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defer dbusMu.Unlock()
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if dbusInited && rootless != dbusRootless {
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panic("can't have both root and rootless dbus")
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}
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dbusInited = true
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dbusRootless = rootless
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return &dbusConnManager{}
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}
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// getConnection lazily initializes and returns systemd dbus connection.
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func (d *dbusConnManager) getConnection() (*systemdDbus.Conn, error) {
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// In the case where dbusC != nil
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// Use the read lock the first time to ensure
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// that Conn can be acquired at the same time.
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dbusMu.RLock()
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if conn := dbusC; conn != nil {
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dbusMu.RUnlock()
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return conn, nil
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}
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dbusMu.RUnlock()
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// In the case where dbusC == nil
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// Use write lock to ensure that only one
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// will be created
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dbusMu.Lock()
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defer dbusMu.Unlock()
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if conn := dbusC; conn != nil {
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return conn, nil
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}
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conn, err := d.newConnection()
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if err != nil {
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// When dbus-user-session is not installed, we can't detect whether we should try to connect to user dbus or system dbus, so d.dbusRootless is set to false.
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// This may fail with a cryptic error "read unix @->/run/systemd/private: read: connection reset by peer: unknown."
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// https://github.com/moby/moby/issues/42793
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return nil, fmt.Errorf("failed to connect to dbus (hint: for rootless containers, maybe you need to install dbus-user-session package, see https://github.com/opencontainers/runc/blob/master/docs/cgroup-v2.md): %w", err)
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}
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dbusC = conn
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return conn, nil
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}
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func (d *dbusConnManager) newConnection() (*systemdDbus.Conn, error) {
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if dbusRootless {
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return newUserSystemdDbus()
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}
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return systemdDbus.NewWithContext(context.TODO())
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}
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// resetConnection resets the connection to its initial state
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// (so it can be reconnected if necessary).
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func (d *dbusConnManager) resetConnection(conn *systemdDbus.Conn) {
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dbusMu.Lock()
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defer dbusMu.Unlock()
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if dbusC != nil && dbusC == conn {
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dbusC.Close()
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dbusC = nil
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}
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}
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var errDbusConnClosed = dbus.ErrClosed.Error()
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// retryOnDisconnect calls op, and if the error it returns is about closed dbus
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// connection, the connection is re-established and the op is retried. This helps
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// with the situation when dbus is restarted and we have a stale connection.
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func (d *dbusConnManager) retryOnDisconnect(op func(*systemdDbus.Conn) error) error {
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for {
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conn, err := d.getConnection()
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if err != nil {
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return err
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}
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err = op(conn)
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if !isDbusError(err, errDbusConnClosed) {
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return err
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}
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d.resetConnection(conn)
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}
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}
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